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Yesterday's closing prices of 2,420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

Folks, please write the answer with all the steps. The answer is clear cut but the only thing I'm interested in is the interpretation of the word problem and the respective approach to solve it. Thanks.If any body used tabular approach, i will be glad to see it because i had trouble solving this problem with the same.

Yesterday's closing prices of 2420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price than yesterday was 20% greater than number that closed at lower price.How many of the stocks closed at a higher price than yesterday?

a)484b)726c)1100d)1320e)1694

Source :OG-13; Q71(PS)

Folks, please write the answer with all the steps. The answer is clear cut but the only thing I'm interested in is the interpretation of the word problem and the respective approach to solve it. Thanks.If any body used tabular approach, i will be glad to see it because i had trouble solving this problem with the same.

Yesterday's closing prices of 2,420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

(A) 484(B) 726(C) 1,100(D) 1,320(E) 1,694

APPROACH #1:

Say x is the number of stocks that closed at a lower price, then 1.2x is the number of stocks that closed at a higher price. Since the total number of stocks is 2,420, then x+1.2x=2,420 --> x=1,100, so 1.2x=1,320.

Answer: D.

APPROACH #2:

If the number of stocks that closed at a lower price were the same as the number of stocks that closed at a higher price, then the number of stocks that closed at a higher price would be 2,420/2=1,210. Since we know that more stocks closed at a higher price than at a lower price than the answer must be greater than 1,210: eliminate A, B, and C. Now, E cannot be correct, because in this case 1,694 closed at a higher price and ~700 closed at a lower price, but 1,694 is obviously not 20% greater than ~700, so we are left with D.

Lets consider the below - The number of stocks that closed at a higher price = HThe number of stocks that closed at a lower price = LWe understand from first statement -> H+L = 2420 ----(1)We understand from second statement -> H = (120/100)L => H = 1.2L ----(2)

Solve eq (1) & (2) to get H = 1320.D is my answer.

Questions, Pls let me know. Cheers! _________________

-----------------------------------------------------------------------------------------What you do TODAY is important because you're exchanging a day of your life for it!-----------------------------------------------------------------------------------------

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Can someone please clarify...

Naren

The correct ratio is closer to 55% - 45% not 60% - 40%

The 20% isn't based off of the total amount of stocks, it's based off of the amount that closed higher vs those that closed lower... so rather than there being a difference of 20% of the TOTAL (60-40) there's a difference of 20% of each position which is closer to only 10% of the total.

When you say that the 20% is based off of the amount that closed higher vs that closed lower.....did all stocks not change value??..so 100% changed values right? so 20% of 100% right...am sorry...I am usually not this confused...but here I am....I am waiting for that ahaa moment I guess and it all becomes clear...

any help is greatly appreciated...

the question states that there are 20% more stocks that closed higher today than stocks that closed lower today.

Stocks cannot close both higher and lower. Therefore the 20% increase is not based off of the total amount, only off of the amount that closed higher...

You're reading the question as if it read 20% more stocks closed higher today than closed higher yesterday... in which case the answer would be unsolvable because we don't know how many closed higher yesterday.

I'm having a huge problem understanding the solution for some reason. I do not understand why 1.2x+x=2420

So there are 2 420 stocks. Yesterday X were sold at lower price and Y and higher price.

So today I know that stocks sold at a higher price are 20 percent more than stocks sold at a lower price yesterday. Which would indeed give me 1.2X but! Don't I need to have another unknown? 1.2X + z = 2 420. as Z would represent number of stocks sold at higher price today. So I do not see why we get 1.2x + x as we did not use X for today's number of stocks sold at lower price.

I must be missing the important point. If someone could explain I'd be very thankful.

There are total of 2,420 stocks, out of them the number of stocks that closed at a higher price than yesterday was 20% greater than number that closed at lower price.

Say x is the number of stocks that closed at a lower priceTODAY, then 1.2x is the number of stocks that closed at a higher priceTODAY. Since the total number of stocks is 2,420, then x+1.2x=2,420 --> x=1,100, so 1.2x=1,320.

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Can someone please clarify...

Naren

The correct ratio is closer to 55% - 45% not 60% - 40%

The 20% isn't based off of the total amount of stocks, it's based off of the amount that closed higher vs those that closed lower... so rather than there being a difference of 20% of the TOTAL (60-40) there's a difference of 20% of each position which is closer to only 10% of the total.

Hence 60% of the 2420 closed higher which gives me 1452....this was not part of the answer choice ...so I eliminated and chose 1320...but I am still confused why this thought process is wrong...

Can someone please clarify...

Naren

The correct ratio is closer to 55% - 45% not 60% - 40%

The 20% isn't based off of the total amount of stocks, it's based off of the amount that closed higher vs those that closed lower... so rather than there being a difference of 20% of the TOTAL (60-40) there's a difference of 20% of each position which is closer to only 10% of the total.

When you say that the 20% is based off of the amount that closed higher vs that closed lower.....did all stocks not change value??..so 100% changed values right? so 20% of 100% right...am sorry...I am usually not this confused...but here I am....I am waiting for that ahaa moment I guess and it all becomes clear...

I'm having a huge problem understanding the solution for some reason. I do not understand why 1.2x+x=2420

So there are 2 420 stocks. Yesterday X were sold at lower price and Y and higher price.

So today I know that stocks sold at a higher price are 20 percent more than stocks sold at a lower price yesterday. Which would indeed give me 1.2X but! Don't I need to have another unknown? 1.2X + z = 2 420. as Z would represent number of stocks sold at higher price today. So I do not see why we get 1.2x + x as we did not use X for today's number of stocks sold at lower price.

I must be missing the important point. If someone could explain I'd be very thankful.

You're reading the question as if it read 20% more stocks closed higher today than closed higher yesterday... in which case the answer would be unsolvable because we don't know how many closed higher yesterday.

I just made the same mental error, so I just wanted to thank tsnarendran for asking, and dave785 for answering! (Kudos given, of course.)

Yesterday's closing prices of 2420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent higher than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

A. 484B. 726C. 1100D. 1320E. 1694

Also I have gone through the answer explanation from OG. I am confused about the phrase 'higher price today than yesterday....'. Does it imply that we have to consider the difference between higher stocks of today and yesterday?? Same goes for lower price shares.

Yesterday's closing prices of 2420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent higher than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

A. 484B. 726C. 1100D. 1320E. 1694

Also I have gone through the answer explanation from OG. I am confused about the phrase 'higher price today than yesterday....'. Does it imply that we have to consider the difference between higher stocks of today and yesterday?? Same goes for lower price shares.

Yesterday's closing prices of 2,420 different stocks listed on a certain stock exchange were all different from today's closing prices. The number of stocks that closed at a higher price today than yesterday was 20 percent greater than the number that closed at a lower price. How many of the stocks closed at a higher price today than yesterday?

Folks, please write the answer with all the steps. The answer is clear cut but the only thing I'm interested in is the interpretation of the word problem and the respective approach to solve it. Thanks.If any body used tabular approach, i will be glad to see it because i had trouble solving this problem with the same.